


you look like you want him forever

by Otpismyoxygen



Series: Atsumu's Sun and Osamu's Moon [1]
Category: Haikyuu!!
Genre: Alternate Universe - Canon Divergence, Established Relationship, M/M, atsumu is so whipped, osamu being a supportive brother, why atsuhina is so underrated
Language: English
Status: Completed
Published: 2019-10-06
Updated: 2019-10-06
Packaged: 2020-11-26 03:48:30
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,151
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20923670
Author URL: https://archiveofourown.org/users/Otpismyoxygen/pseuds/Otpismyoxygen
Summary: Osamu watched his twin brother fall hard for Karasuno's number ten.





	you look like you want him forever

**Author's Note:**

> Happy Atsuhina day 10/7! and also, happy birthday to the best twins <3

Osamu never saw his twin _this_ in love for as long as he could remember. And he had been with him since he was born.

It wasn't that his beloved twin never dated. In fact, he dated quite a handful of people. After all, Atsumu was a people person. He loved being around people, he loved touches, he loved affection, and he just loved… people.

In conclusion, it wasn't a mistake that people called his twin the "jock" of the school. Maybe even of their prefecture. Or maybe of the whole Japan. Miya Atsumu was the number one high school setter, for crying out loud. Many people admired him (and hated him). He had always been the center of attention.

Osamu couldn't be more glad that his literal other half had sucked all everyone's attention to him. Osamu hated attention thank you very much.

That was why their relationship was perfect. Some people said that they were so different, but Osamu thought that their difference was probably the thing that made them a functional pair of twins.

Despite all that difference, though, they knew each other like no one's business.

Osamu knew Atsumu's bad habit, Atsumu knew Osamu's most hated thing in the world. Osamu knew what was his twin's insecurities, Atsumu knew his biggest weakness. Osamu knew what Atsumu truly liked, Atsumu knew Osamu's dreams.

They were just like any typical twins in the world. They knew each other very well. Too well.

Maybe that was why Osamu could tell almost immediately. The moment it happened, the moment his brother fell in love, he just knew.

At first, it looked just like an admiration or fixation. After all, it was so hard to not focus on Karasuno's number ten. The redhead just had that magnet, a tremendous aura of _ look-at-me _ so strong that it compelled everyone around him to pay attention to him.

That _ everyone _ included his twin. And honestly, Osamu didn't blame Atsumu. He, too, was almost drawn to the short guy, but Osamu could stop himself. His twin though, was a different case. Because Osamu could see how Atsumu let himself being drawn. He wasn't even trying to stop himself.

At that time, Osamu didn't think that it was a special case at all. Atsumu had declared his interest in multiple spikers beforehand. _ I want to toss to you. I want to play together with you. I think it'll be great if we can play sometime. _ So Atsumu's _ Shouyo, I'll toss to you one of these days _ that had been said to Karasuno's little decoy after their loss to the crow team in the second round of Spring High Nationals on the second year of their high school didn't spark Osamu as something odd at that time. And Osamu thought it was fair. They were still seventeen, so it never crossed Osamu's mind, not even the slightest, that it was the start of it all.

The start of his twin's forever.

Throughout the whole game, Osamu never caught the little guy's name. He was always bad at it. But by the time they came back to their hometown after Nationals ended, the Karasuno's number ten's name had been ingrained into his memory that he was sure that he wouldn't forget it for the next ten years because of how many time his twin had mentioned the name to Osamu on the whole way back to their town.

Shouyo.

Hinata Shouyo.

At that point, Osamu should've known. He should've been able to pick up the hint. But maybe he was too dense. Or maybe he was too tired of the long journey back home after the infamous hectic Nationals. Or maybe he didn't take it too seriously at that time. But he should've known, that his twin had never talked about someone _this_ much. So it must meant something. A huge thing.

But Osamu shrugged it off. Only for now.

What Osamu realized, because the fact was glaring so blatantly at him, after they went back to their daily activity, was that his twin started to play with his phone more often. Almost all the time. And while grinning so stupidly at the device.

Still, Osamu shrugged it off.

But then he realized that Atsumu had also started to make phone calls more often. Osamu was never able to catch who he was calling, and he really couldn't recognize the faint voice that could be heard from the other side of the line either.

Osamu started to wonder. But, oh well.

What was the most strange was when his twin started to buy things that Osamu knew was impossible that they were for himself. T-shirts, notebook, socks, sweets, keychains, and even dolls. All those things, Osamu never saw them being used by his twin. So the only answer was that they were given to someone else.

That was when Osamu _finally_ voiced his curiosity. "Are you going out with someone?"

The look on his twin's face was priceless. It wasn't like he was embarrassed, or even surprised, but more like confused.

"Huh? I haven't told you yet?" Atsumu's raised his brows.

"I wouldn't ask you if I already knew."

Atsumu cringed at that. His hand reached to tug through his ugly blond hair, messing it up a little. And only then that Osamu could see the shyness crept into his twin's face. Atsumu blushed.

_Blushed._

Good God.

Ew.

"Yeah, I'm sort of… dating."

The answer didn't really surprise Osamu. "Sort of?"

"I haven't confessed to them in person yet. Only through phone call." Atsumu glanced at Osamu for a second, before he averted his gaze. "I know it's lame, don't judge me."

"I'm not saying anything. Why didn't you confess in person, then?"

Atsumu groaned. Now he was kicking the ground, and his head was thrown back until it hit the wall. "I'm still saving my money, that's why. The train ticket to Miyagi isn't cheap, you know."

"Wait, what?" Now _this_ was something new. Osamu never expected this. "Miyagi?"

Atsumu didn't immediately answer. His confused expression was back, as he blinked at Osamu. "Yes, Miyagi. Shouyo was from Miyagi, remember?"

Osamu didn't remember, of course, why would he. And the mention of that particular name somehow surprised, and didn't surprise him at all at the same time.

So it was Shouyo.

Of course it was Shouyo.

Who else could it be?

Once again. Osamu should've known.

For the next weeks after that, Osamu watched his twin _ sort-of-dating _ Karasuno's decoy, although Atsumu still called Shouyo _ my boyfriend _all the same. But it was great. Seeing his brother being so smitten was great. Osamu basically had a field day teasing his whipped twin brother.

Osamu had watched his twin dating numerous times. But it was different this time. Of course it was. This was Shouyo they were talking about after all. He was special, as Atsumu said it.

The Atsumu who was dating Shouyo was… happy. He smiled almost all the time. He was friendly to everyone. He no longer picked a fight with Osamu.

The Atsumu who was dating Shouyo was, dare Osamu say, the best version of Atsumu. As a volleyball player, he trained even better now because he wanted to be a better setter, for Shouyo, in the future. As a twin brother, he never bothered Osamu again with unnecessary things because he had Shouyo now who would accept all his bullshit with open arms. As a person, he became someone who was even more liked by people because he emitted this flowery, happy aura that sometimes made Osamu want to gag. And as a boyfriend...

For short, Osamu never expected that his twin brother was capable to be this kind of romantic partner to someone. 

Atsumu was caring. One time, Atsumu received a call from Kageyama, informing him that Hinata collapse while training due to fever, _again_. It sent his twin brother into major panic. He and his twin brother witnessed how bad could it be when Shouyo pushed himself beyond his limit. The memory of Shouyo collapsing at Nationals was enough to make Atsumu almost buying the first ticket to Miyagi. But a phone call from the sick guy succeeded to calm his panicked brother down. Atsumu had bought a ticket to Miyagi beforehand for that weekend for the their scheduled monthly date. So there was no way Shouyo would let his boyfriend come to Miyagi twice in a span of a week. Shouyo said he was okay, he apologized to a furious Atsumu who was so worried out of his mind, he said he missed Atsumu and couldn't wait to see him soon in a few days. And Atsumu spent the rest of the week making sure that his stubborn, sick boyfriend was getting enough rest through phone calls and messages.

Atsumu loved to spoil. When he was out with Osamu, or with the team, or with his classmates, or with his friends, if he saw something remotely cute, he would buy it. Osamu never asked because he knew, but other people usually did, "who is it for?" since there was no way it was for Atsumu himself. Then his twin brother would answer with sparkling eyes, along with his disgusting smitten smile on, "For my cute boyfriend." Now, people never really asked anymore, because they just knew, it was for his boyfriend. In fact, some of them now sometimes recommended some stuff to Atsumu, saying something like, "Hey, Atsumu, you can give this to your cute boyfriend." That was how much Atsumu talk about Shouyo. Everyone knew Shouyo, someone who was so far away, even though some of them never met him.

Atsumu was supportive. Osamu thought that this was the first time he saw his twin showing some sort of support to a player other than his own teammates. Atsumu was often seen as a dick sometimes, due to his godly skill that put him above all else. But toward Shouyo, he put his utmost support. Dating someone younger meant that his twin needed to be the mature one, and even though in Osamu's eyes his brother was as childish as ever, he was different with Shouyo. The Karasuno's decoy had a lot of insecurities, selfish yet driven thought, and Atsumu was always there to help him go through it all, making sure that his boyfriend knew that he was, indeed, special. Osamu thought he was pretty good at doing it.

When Shouyo's team finally won the Spring Tournament in their prefecture, and got another ticket to Nationals by the time their relationship almost reached its one year anniversary mark, Osamu never saw his twin brother this happy. Not even when his own team won, but then it was because Atsumu was so confident on bringing his team to Nationals before he graduated.

Atsumu almost cried when he received the news through the phone. Osamu saw how wet his eyes were although his smile was so wide it almost broke his face.

It had been one of Atsumu's wishes, to be given the last chance to go against his boyfriend in the official match in their high school year.

Osamu's remember his twin's _ I'll toss to you one of these days _ and he couldn't help but feel happy too for his brother and his boyfriend. This would be another step forward toward that goal. They deserve this. Shouyo trained and improved so much so that he could be considered on the same level as Atsumu. And Atsumu in return also trained harder so he could be at least match his boyfriend's amazing play.

If someone asked Osamu, his twin brother's relationship with Shouyo was the best relationship that anyone could have.

To think that love could bring out the best from his brother, Osamu really needed to thank Shouyo.

Which was why he followed his brother who was going to see Shouyo before the Nationals opening ceremony. He wanted to see his twin's boyfriend and possibly thank him for all he had done for his brother, whether he realized it or not.

Osamu hadn't seen Shouyo since last year Spring High, while his brother had multiple times visited Miyagi to come see him. So it was a nice surprise seeing how much the little guy had changed throughout the year. The most blatant different was the way he light up when he landed his eyes on Atsumu, amidst all the crowd around them during the first day of Nationals.

It was kind of weird. The last time Osamu saw Shouyo was when they were rivals. And now, he saw how Shouyo looked at Atsumu like he was the world.

Osamu then looked at his brother, and he smiled, because he realized this was also the first time he witnessed it first hand how his twin brother was in front of his _ cute boyfriend. _

Atsumu looked at Shouyo like he wanted him forever.

**Author's Note:**

> Please give atsuhina a lot of love they deserve it.


End file.
